Approximately one third of infants with infantile esotropia (infantile ET) and a similar proportion of children with acquired non-accommodative esotropia (ANAET) will have an increasing angle within the first few months of their initial examination. In approximately two thirds of patients, the angle of misalignment remains stable and in a small proportion, the angle of esotropia decreases. The changing angle of misalignment in a significant proportion of children with esotropia raises an important question regarding the timing of surgical management of these children: should surgery be undertaken immediately or delayed until the alignment stabilizes? Early surgery may improve sensory outcomes; delayed surgery may improve surgical dosing accuracy and motor outcomes.